Case Study: Whole Foods, San Jose

Whole Foods Market in San Jose, California, highlights Unison Energy’s expertise in the Supermarket arena. Whole Foods was looking for an energy solution to support their corporate sustainability goals while helping to reduce overall operating costs. One of the challenges for this site was space and the integration of Unison’s CHP with a Hillphoenix provided CO2 based refrigeration system and HVAC / heating loop that was to provide the store and integrated brewery with a leading edge environmentally friendly energy package.

Unison Energy’s solution: a roof-mounted CHP system consisting of 2 x 165kW reciprocating natural gas engines with heat exchangers connected to a Unison integrated absorption chiller and hot water loop to a roof-mounted Hillphoenix advanced supermarket refrigeration/HVAC system. The absorption powered chilled water loop provides 60 tons of chilled water to supplement Hillphoenix’s new environmentally friendly transcritical CO2 based refrigeration system used by the stores medium – and low – temperature cases while the hot water loop supplements the integrated HVAC / domestic hot water systems. In addition, and keeping with Whole Foods environmental focus, Unison installed adiabatic cooling towers that reduced cooling water use by up to 90%.

The resulting refrigeration solution has been jointly patented with Hillphoenix and the overall energy solution received California SGIP funding. The combination of CHP plus the CO2 based refrigeration system and integrated HVAC / heating loop resulted in one of the most energy efficient and environmentally sustainable stores within Whole Foods.